Climate model projections suggest major North American biome shifts in response to anthropogenic climate change (Rehfeldt et al. 2012). Such shifts could have profound influences on native flora and fauna, many of which would have to move long distances to track their climatic niches. To evaluate potential ecosystem changes at a somewhat finer scale, I projected the change in climate space for level III ecoregions (Commission for Environmental Cooperation 1997) as surrogates for multiple associated species and ecological communities. First, I developed a random forest model (Breiman 2001) to predict ecoregion class from bioclimatic variables (Table 1), using 1-km interpolated climate data for the 1969-1990 normal period (Hamann et al. 2013), available at http://adaptwest.databasin.org.
R Code for this portion follows:
library(randomForest)
library(raster)
#eco = project directory
setwd(eco)
datlcc = read.csv("CECEcoregionSampleLCC.csv")
cececo = read.csv("CECecoregions.csv")
LCC <- CRS("+proj=lcc +lat_1=49 +lat_2=77 +lat_0=0 +lon_0=-95 +x_0=0 +y_0=0 +ellps=GRS80 +units=m +no_defs")
#cur = directory containing grids representing derived climate variables
setwd(cur)
clim <- list.files(cur, pattern =".asc$")
curclim<-stack(clim)
temp <- raster(clim[1])
ID <- as.data.frame(rasterToPoints(temp))
names(ID)[3] <- "ID4km"
ID$ID <- row.names(ID)
IDR <- raster(ncols=ncol(temp), nrows=nrow(temp), xmn=xmin(temp), xmx=xmax(temp), ymn=ymin(temp), ymx=ymax(temp))
IDRR <- rasterize(as.matrix(ID[,1:2]), IDR, as.numeric(ID[,4]))
curclim <- addLayer(curclim,IDRR)
setwd(eco)
sampleclim<-cbind(datlcc,extract(curclim,as.matrix(cbind(datlcc[,3],datlcc[,4]))))
sc <- na.omit(sampleclim)
names(sc)[ncol(sc)] <- "IDgrid"
sc$NA_L3CODE <- as.factor(as.character(sc$NA_L3CODE))
lu <- as.data.frame(levels(sc$NA_L3CODE))
lu$level <- row.names(lu)
names(lu)[1] <- "NA_L3CODE"
write.csv(lu,file="ecoregionlu.csv",row.names=FALSE)
eco.rf <- randomForest(y=sc$NA_L3CODE, x=sc[,5:(ncol(sc)-1)],importance = TRUE, proximity = TRUE, data=sc)
round(importance(eco.rf), 2)
varImpPlot(eco.rf)
ecocurr <- predict(curclim,eco.rf)
projection(ecocurr) <- LCC
writeRaster(ecocurr,filename="currentlcc.tif",datatype='INT4S',format="GTiff",overwrite=TRUE)
curfreq <- freq(ecocurr)
ecolu <- merge(lu,curfreq,by.x="level",by.y="value")
names(ecolu)[3] <- "curr"
Table 1: Bioclimatic variables used as inputs to random forest models (from Hamann et al. 2013)
MAT: mean annual temperature (°C)
MWMT: mean temperature of the warmest month (°C)
MCMT: mean temperature of the coldest month (°C)
TD: difference between MCMT and MWMT, as a measure of continentality (°C)
MAP: mean annual precipitation (mm)
MSP: mean summer (May to Sep) precipitation (mm)
AHM: annual heat moisture index, calculated as (MAT+10)/(MAP/1000)
SHM: summer heat moisture index, calculated as MWMT/(MSP/1000)
DD0: degree-days below 0°C (chilling degree days)
DD5: degree-days above 5°C (growing degree days)
DD18: degree-days below 18°C
DD18: degree-days above 18°C
NFFD: the number of frost-free days
bFFP: the julian date on which the frost-free period begins
eFFP: the julian date on which the frost-free period ends
FFP: frost-free period
PAS: precipitation as snow (mm)
EMT: extreme minimum temperature over 30 years
EXT: extreme maximum temperature over 30 years
Eref: Hargreave’s reference evaporation
CMD: Hargreave’s climatic moisture index
RH: mean annual relative humidity (%)
Tavewt: winter (Dec to Feb) mean temperature (°C)
Tavesm: summer (Jun to Aug) mean temperature (°C)
PPTwt: winter (Dec to Feb) precipitation (mm)
PPTsm: summer (Jun to Aug) precipitation (mm)
This model was then used to project ecoregions onto future mid-century (2041-2070) and end-of-century (2071-2100) climate conditions. Climate projections were based on 1-km downscaled climate anomalies (Wang et al. 2016) generated by an ensemble of 15 widely-used GCMs from the Coupled Model Intercomparison Project, Phase 5 (CMIP5, Taylor et al. 2012), available at http://adaptwest.databasin.org. I used representative concentration pathway (RCP) 8.5, to represent the 21st century conditions that are to be expected without dramatic reductions in greenhouse gas emissions or technological fixes (Fuss et al. 2014). I also evaluated RCP 4.5 to represent a future in which significant emissions reductions are achieved.
The following code generates projections for each representative and time period:
fut = directory containing grids representing derived future climate variables
rcp <- c("rcp45","rcp85")
time <- c("2050s","2080s")
for (j in rcp) {
for (k in time) {
w <- paste(fut,"NA_ENSEMBLE_",j,"_",k,"_Bioclim_ASCII/",sep="")
setwd(w)
futclim <- list.files(w,pattern=".asc$")
s <-stack(futclim)
p <- predict(s,eco.rf)
projection(p) <- LCC
futfreq <- as.data.frame(freq(p))
names(futfreq)[2] <- paste(i,j,sep="_")
ecolu <- merge(ecolu,futfreq,by.x="level",by.y="value")
writeRaster(p, filename=paste(eco,"pred",j,k,sep="_"),datatype='INT4S',format="GTiff", overwrite=TRUE)
}
}
Results for RCP 4.5 and RCP 8.5 are shown in Figures 1 and 2, respectively:
Figure 1. Model-predicted (a) baseline, (b) mid-century, and (c) end-of-century changes in North American ecoregions for RCP 4.5. Boreal, hemi-boreal, and western forested regions are shown in green and blue-green shades; arctic ecoregions are in blue shades; prairie/parkland ecoregions are in brown shades; and temperate forest ecoregions are in yellow and orange shades (see Table 1 for full list of ecoregions). Boreal ecoregions are also outlined in black.
Figure 2. Model-predicted (a) baseline, (b) mid-century, and (c) end-of-century changes in North American ecoregions for RCP 8.5. Boreal, hemi-boreal, and western forested regions are shown in green and blue-green shades; arctic ecoregions are in blue shades; prairie/parkland ecoregions are in brown shades; and temperate forest ecoregions are in yellow and orange shades (see Table 1 for full list of ecoregions). Boreal ecoregions are also outlined in black.
Next, I used the following code to calculate the change in area (16 km2 pixels) for each Level III ecoregion (Table 2):
groups <- c("rcp45_2050s","rcp45_2080s","rcp85_2050s","rcp85_2080s")
setwd(eco)
for (i in groups) {
g <- list.files(eco,pattern=i)
g1 <- grep(pattern=".tif$",g,value=TRUE)
m <- raster(g1)
futfreq <- as.data.frame(freq(m))
names(futfreq)[2] <- i
ecolu <- merge(ecolu,futfreq,by.x="level",by.y="value")
}
ecolu1 <- merge(unique(cececo[,c(2:4)]),ecolu[,2:7],by="NA_L3CODE")
write.csv(ecolu1,file="ecoregion_changesummary.csv",row.names=FALSE)
Table 2. Model-projected changes by ecoregion (sq km):
| NA_L3CODE | NA_L3NAME | curr | rcp45_2050s | rcp45_2080s | rcp85_2050s | rcp85_2080s |
|---|---|---|---|---|---|---|
| 1.1.2 | Baffin and Torngat Mountains | 147147 | 256752 | 278424 | 235507 | 106740 |
| 10.1.1 | Thompson-Okanogan Plateau | 79481 | 128181 | 102991 | 93853 | 17523 |
| 10.1.2 | Columbia Plateau | 87319 | 128349 | 130511 | 133438 | 92006 |
| 10.1.3 | Northern Basin and Range | 163503 | 52087 | 28000 | 26510 | 2500 |
| 10.1.4 | Wyoming Basin | 142375 | 20672 | 10308 | 8748 | 317 |
| 10.1.5 | Central Basin and Range | 248329 | 178117 | 161763 | 171074 | 44943 |
| 10.1.6 | Colorado Plateaus | 148135 | 410063 | 445829 | 458570 | 479993 |
| 10.1.7 | Arizona/New Mexico Plateau | 170714 | 215623 | 216068 | 215201 | 137227 |
| 10.1.8 | Snake River Plain | 71248 | 34098 | 22125 | 20400 | 1620 |
| 10.2.1 | Mojave Basin and Range | 145279 | 178168 | 214764 | 239676 | 559531 |
| 10.2.2 | Sonoran Desert | 249917 | 313014 | 308390 | 333780 | 477826 |
| 10.2.3 | Baja Californian Desert | 125247 | 108494 | 133306 | 143065 | 130262 |
| 10.2.4 | Chihuahuan Desert | 560769 | 634266 | 615488 | 614688 | 512968 |
| 11.1.1 | California Coastal Sage, Chaparral, and Oak Woodlands | 118844 | 119971 | 124429 | 124621 | 148146 |
| 11.1.2 | Central California Valley | 59912 | 55961 | 47599 | 41428 | 920 |
| 11.1.3 | Southern and Baja California Pine-Oak Mountains | 40794 | 52147 | 49068 | 48033 | 34558 |
| 12.1.1 | Madrean Archipelago | 119798 | 120764 | 113420 | 110430 | 109247 |
| 12.1.2 | Piedmonts and Plains with Grasslands, Xeric Shrub, and Oak and Conifer Forests | 225107 | 159305 | 140803 | 136965 | 67801 |
| 12.2.1 | Hills and Interior Plains with Xeric Shrub and Mesquite Low Forest | 117722 | 115409 | 104551 | 100841 | 60874 |
| 13.1.1 | Arizona/New Mexico Mountains | 119795 | 121932 | 125652 | 120830 | 138375 |
| 13.2.1 | Sierra Madre Occidental with Conifer, Oak, and Mixed Forests | 203850 | 129997 | 119021 | 106488 | 64358 |
| 13.3.1 | Sierra Madre Oriental with Conifer, Oak, and Mixed Forests | 99879 | 112527 | 125093 | 125837 | 102492 |
| 13.4.1 | Interior Plains and Piedmonts with Grasslands and Xeric Shrub | 30155 | 13136 | 9148 | 8526 | 1347 |
| 13.4.2 | Hills and Sierras with Conifer, Oak, and Mixed Forests | 90230 | 56118 | 46624 | 41800 | 21474 |
| 13.5.1 | Sierras of Jalisco and Michoacan with Conifer, Oak, and Mixed Forests | 45189 | 29437 | 30622 | 27347 | 19195 |
| 13.5.2 | Sierras of Guerrero and Oaxaca with Conifer, Oak, and Mixed Forests | 93219 | 56589 | 51279 | 46021 | 21458 |
| 13.6.1 | Central American Sierra Madre with Conifer, Oak, and Mixed Forests | 24543 | 10157 | 8224 | 8785 | 2653 |
| 13.6.2 | Chiapas Highlands with Conifer, Oak, and Mixed Forest | 47734 | 30717 | 26910 | 25142 | 11528 |
| 14.1.1 | Coastal Plain with Low Tropical Deciduous Forest | 45021 | 67157 | 58930 | 52306 | 26294 |
| 14.1.2 | Hills and Sierra with Low Tropical Deciduous Forest and Oak Forest | 32934 | 27023 | 22562 | 21273 | 9515 |
| 14.2.1 | Northwestern Yucatan Plain with Low Tropical Deciduous Forest | 21348 | 31181 | 43435 | 42619 | 120368 |
| 14.3.1 | Sinaloa Coastal Plain with Low Thorn Tropical Forest and Wetlands | 55351 | 184089 | 253772 | 303349 | 693883 |
| 14.3.2 | Sinaloa and Sonora Hills and Canyons with Xeric Shrub and Low Tropical Deciduous Forest | 116252 | 161186 | 188683 | 190719 | 386533 |
| 14.4.1 | Balsas Depression with Low Tropical Deciduous Forest and Xerophytic Shrub | 94443 | 142241 | 155449 | 167393 | 217971 |
| 14.4.2 | Chiapas Depression with Low Deciduous and Medium Semi-Deciduous Tropical Forest | 27227 | 13295 | 11191 | 10296 | 9580 |
| 14.4.3 | Valleys and Depressions with Xeric Shrub and Low Tropical Deciduous Forest | 27146 | 38202 | 36891 | 37294 | 35815 |
| 14.5.1 | Tehuantepec Canyon and Plain with Low Tropical Deciduous Forest and Low Thorn Tropical Forest | 19737 | 41575 | 43559 | 41086 | 52429 |
| 14.5.2 | South Pacific Hills and Piedmonts with Low Tropical Deciduous Forest | 66703 | 85395 | 99426 | 102297 | 119513 |
| 14.6.1 | Los Cabos Plains and Hills with Low Tropical Deciduous Forest and Xeric Shrub | 16353 | 42909 | 43769 | 41573 | 23672 |
| 14.6.2 | La Laguna Mountains with Oak and Conifer Forest | 2570 | 1344 | 1185 | 1126 | 501 |
| 15.1.1 | Gulf of Mexico Coastal Plain with Wetlands and High Tropical Rain Forest | 92436 | 160749 | 153390 | 154527 | 136595 |
| 15.1.2 | Hills with Medium and High Evergreen Tropical Forest | 106764 | 75092 | 81041 | 90784 | 119204 |
| 15.2.1 | Plain with Low and Medium Deciduous Tropical Forest | 63136 | 123240 | 125750 | 130375 | 93831 |
| 15.2.2 | Plain with Medium and High Semi-Evergreen Tropical Forest | 46630 | 34045 | 29748 | 22123 | 2786 |
| 15.2.3 | Hills with High and Medium Semi-Evergreen Tropical Forest | 78883 | 5709 | 6137 | 5979 | 6417 |
| 15.3.1 | Los Tuxtlas Sierra with High Evergreen Tropical Forest | 10762 | 2087 | 1633 | 1416 | 13724 |
| 15.4.1 | Southern Florida Coastal Plain | 38967 | 74884 | 83614 | 78635 | 40314 |
| 15.5.1 | Nayarit and Sinaloa Plain with Low Thorn Tropical Forest | 9738 | 2650 | 1532 | 1425 | 1651 |
| 15.5.2 | Jalisco and Nayarit Hills and Plains with Medium Semi-Evergreen Tropical Forest | 20266 | 42203 | 49771 | 52308 | 75866 |
| 15.6.1 | Coastal Plain and Hills with High and Medium-High Evergreen Tropical Forest and Wetlands | 20201 | 25035 | 18554 | 17797 | 7691 |
| 2.1.4 | Lancaster and Borden Peninsula Plateaus | 153401 | 100458 | 57518 | 52380 | 2 |
| 2.1.5 | Foxe Uplands | 359792 | 172936 | 212147 | 159876 | 76162 |
| 2.1.6 | Baffin Uplands | 148664 | 39067 | 32090 | 28237 | 22447 |
| 2.1.7 | Gulf of Boothia and Foxe Basin Plains | 147691 | 94997 | 44196 | 30062 | 4356 |
| 2.1.9 | Banks Island and Amundsen Gulf Lowlands | 160336 | 239188 | 224215 | 194489 | 15065 |
| 2.2.1 | Arctic Coastal Plain | 58756 | 95 | 2266 | 5255 | 22959 |
| 2.2.2 | Arctic Foothills | 123434 | 235933 | 305118 | 459436 | 119091 |
| 2.2.3 | Subarctic Coastal Plains | 100808 | 229447 | 323128 | 388110 | 1281925 |
| 2.2.4 | Seward Peninsula | 59337 | 156920 | 256979 | 281469 | 286106 |
| 2.2.5 | Bristol Bay-Nushagak Lowlands | 63649 | 106118 | 103595 | 106972 | 389553 |
| 2.2.6 | Aleution Islands | 12993 | 4767 | 2467 | 2058 | 1132 |
| 2.4.1 | Amundsen Plains | 285721 | 491512 | 345481 | 217998 | 44812 |
| 2.4.3 | Central Ungava Peninsula and Ottawa and Belcher Islands | 168795 | 136014 | 90049 | 83728 | 57559 |
| 3.1.1 | Interior Forested Lowlands and Uplands | 154744 | 214494 | 244642 | 302972 | 397504 |
| 3.1.2 | Interior Bottomlands | 147095 | 104970 | 89188 | 60760 | 24020 |
| 3.1.3 | Yukon Flats | 43564 | 57030 | 38887 | 47545 | 20218 |
| 3.2.1 | Ogilvie Mountains | 78032 | 84458 | 80561 | 67101 | 40699 |
| 3.3.2 | Hay and Slave River Lowlands | 273770 | 329298 | 260311 | 228498 | 88246 |
| 3.4.3 | Smallwood Uplands | 260456 | 72043 | 45379 | 31847 | 8018 |
| 3.4.4 | Ungava Bay Basin and George Plateau | 124658 | 16561 | 15184 | 14273 | 175 |
| 3.4.5 | Coppermine River and Tazin Lake Uplands | 247484 | 278724 | 261461 | 289089 | 3376 |
| 4.1.2 | Hudson Bay and James Bay Lowlands | 277767 | 56692 | 24743 | 18601 | 4711 |
| 5.1.1 | Athabasca Plain and Churchill River Upland | 261634 | 180539 | 172825 | 169140 | 61254 |
| 5.1.2 | Lake Nipigon and Lac Seul Upland | 217842 | 383191 | 334585 | 292786 | 77691 |
| 5.1.3 | Central Laurentians and Mecatina Plateau | 302052 | 319010 | 262655 | 245088 | 61726 |
| 5.1.4 | Newfoundland Island | 125291 | 159633 | 150097 | 145165 | 141949 |
| 5.1.5 | Hayes River Upland and Big Trout Lake | 264910 | 99563 | 68160 | 60244 | 1195 |
| 5.1.6 | Abitibi Plains and Riviere Rupert Plateau | 287990 | 145527 | 142434 | 111390 | 15384 |
| 5.2.1 | Northern Lakes and Forests | 297661 | 550438 | 693642 | 770212 | 567791 |
| 5.2.3 | Algonquin/Southern Laurentians | 350698 | 443628 | 423668 | 436081 | 460129 |
| 5.3.1 | Northern Appalachian and Atlantic Maritime Highlands | 213235 | 297005 | 324996 | 338882 | 484216 |
| 5.3.3 | North Central Appalachians | 40906 | 5581 | 6484 | 7114 | 15510 |
| 5.4.1 | Mid-Boreal Uplands and Peace-Wabaska Lowlands | 384861 | 384235 | 311499 | 240506 | 112622 |
| 5.4.2 | Clear Hills and Western Alberta Upland | 147911 | 76236 | 63250 | 52958 | 8624 |
| 5.4.3 | Mid-Boreal Lowland and Interlake Plain | 137275 | 232935 | 277233 | 324472 | 401337 |
| 6.1.1 | Interior Highlands and Klondike Plateau | 125183 | 86212 | 115739 | 128553 | 19129 |
| 6.1.2 | Alaska Range | 101281 | 86438 | 91774 | 95471 | 35952 |
| 6.1.3 | Copper Plateau | 25317 | 7840 | 1044 | 376 | 21 |
| 6.1.4 | Wrangell and St. Elias Mountains | 58813 | 35893 | 27452 | 23311 | 14394 |
| 6.1.5 | Watson Highlands | 215821 | 109456 | 57769 | 43653 | 6952 |
| 6.1.6 | Yukon-Stikine Highlands/Boreal Mountains and Plateaus | 162769 | 50965 | 43275 | 34939 | 23134 |
| 6.2.1 | Skeena-Omineca-Central Canadian Rocky Mountains | 146470 | 160853 | 135239 | 120210 | 50879 |
| 6.2.10 | Middle Rockies | 161078 | 55926 | 45646 | 40694 | 18262 |
| 6.2.11 | Klamath Mountains | 59290 | 100615 | 113637 | 116533 | 190016 |
| 6.2.12 | Sierra Nevada | 56436 | 44004 | 41467 | 40535 | 22943 |
| 6.2.13 | Wasatch and Uinta Mountains | 95639 | 85060 | 84545 | 82247 | 40683 |
| 6.2.14 | Southern Rockies | 146075 | 79895 | 64838 | 51395 | 25539 |
| 6.2.15 | Idaho Batholith | 74737 | 76608 | 70690 | 73617 | 53969 |
| 6.2.2 | Chilcotin Ranges and Fraser Plateau | 113621 | 7374 | 2090 | 1782 | 122 |
| 6.2.3 | Columbia Mountains/Northern Rockies | 161058 | 252240 | 264915 | 271050 | 274785 |
| 6.2.4 | Canadian Rockies | 106010 | 53214 | 33347 | 23701 | 3133 |
| 6.2.5 | North Cascades | 41160 | 35151 | 31590 | 30225 | 19980 |
| 6.2.6 | Cypress Upland | 22463 | 925 | 2326 | 3179 | 3527 |
| 6.2.7 | Cascades | 48106 | 30917 | 32153 | 30980 | 24273 |
| 6.2.8 | Eastern Cascades Slopes and Foothills | 76924 | 50858 | 39265 | 37516 | 10082 |
| 6.2.9 | Blue Mountains | 81264 | 122265 | 114078 | 110356 | 113839 |
| 7.1.1 | Ahklun and Kilbuck Mountains | 62628 | 210151 | 224034 | 200959 | 32945 |
| 7.1.2 | Alaska Peninsula Mountains | 54947 | 28924 | 27208 | 26629 | 22337 |
| 7.1.3 | Cook Inlet | 31714 | 258308 | 325196 | 360731 | 204427 |
| 7.1.4 | Pacific Coastal Mountains | 109324 | 110053 | 113038 | 112518 | 87051 |
| 7.1.5 | Coastal Western Hemlock-Sitka Spruce Forests | 96025 | 167783 | 176032 | 178428 | 163666 |
| 7.1.6 | Pacific and Nass Ranges | 99230 | 133991 | 150169 | 153362 | 154938 |
| 7.1.7 | Strait of Georgia/Puget Lowland | 48048 | 37542 | 41816 | 44456 | 80267 |
| 7.1.8 | Coast Range | 57502 | 111722 | 124460 | 125210 | 146726 |
| 7.1.9 | Willamette Valley | 19425 | 4945 | 3615 | 3925 | 12446 |
| 8.1.1 | Eastern Great Lakes Lowlands | 185396 | 399806 | 511228 | 563219 | 801293 |
| 8.1.10 | Erie Drift Plain | 54959 | 3115 | 593 | 373 | 182 |
| 8.1.2 | Lake Erie Lowland | 71512 | 71944 | 50905 | 53404 | 21297 |
| 8.1.3 | Northern Allegheny Plateau | 56906 | 1487 | 534 | 560 | 23971 |
| 8.1.4 | North Central Hardwood Forests | 107373 | 103169 | 108931 | 101597 | 237007 |
| 8.1.5 | Driftless Area | 56904 | 27122 | 6541 | 9722 | 56230 |
| 8.1.6 | Southern Michigan/Northern Indiana Drift Plains | 81430 | 23829 | 17145 | 13253 | 417 |
| 8.1.7 | Northeastern Coastal Zone | 61604 | 230818 | 254436 | 245976 | 200520 |
| 8.1.8 | Acadian Plains and Hills | 111308 | 40773 | 46764 | 37862 | 28274 |
| 8.1.9 | Maritime Lowlands | 46701 | 13691 | 12593 | 8969 | 8838 |
| 8.2.1 | Southeastern Wisconsin Till Plains | 41043 | 42756 | 43861 | 32257 | 90658 |
| 8.2.2 | Huron/Erie Lake Plains | 54469 | 85966 | 67329 | 61276 | 28067 |
| 8.2.3 | Central Corn Belt Plains | 92678 | 73997 | 100504 | 140394 | 250957 |
| 8.2.4 | Eastern Corn Belt Plains | 87010 | 39615 | 33682 | 36241 | 8857 |
| 8.3.1 | Northern Piedmont | 42573 | 170005 | 167343 | 153662 | 53715 |
| 8.3.2 | Interior River Valleys and Hills | 131437 | 373661 | 383500 | 408178 | 433738 |
| 8.3.3 | Interior Plateau | 145391 | 60581 | 57552 | 55578 | 50507 |
| 8.3.4 | Piedmont | 199405 | 24230 | 20990 | 15243 | 2166 |
| 8.3.5 | Southeastern Plains | 304687 | 9091 | 6755 | 7501 | 3549 |
| 8.3.6 | Mississippi Valley Loess Plains | 85927 | 13701 | 11629 | 9952 | 22612 |
| 8.3.7 | South Central Plains | 178978 | 701415 | 692767 | 704770 | 611455 |
| 8.3.8 | East Central Texas Plains | 62055 | 166974 | 215681 | 249240 | 433078 |
| 8.4.1 | Ridge and Valley | 85618 | 29098 | 16038 | 10560 | 2334 |
| 8.4.2 | Central Appalachians | 89927 | 51069 | 40889 | 44792 | 66604 |
| 8.4.3 | Western Allegheny Plateau | 83575 | 8479 | 4804 | 3360 | 15 |
| 8.4.4 | Blue Ridge | 51004 | 33856 | 35301 | 35072 | 66437 |
| 8.4.5 | Ozark Highlands | 109761 | 76718 | 42713 | 26546 | 1981 |
| 8.4.6 | Boston Mountains | 24203 | 60902 | 63537 | 39483 | 5440 |
| 8.4.7 | Arkansas Valley | 38145 | 140421 | 168122 | 184531 | 89087 |
| 8.4.8 | Ouachita Mountains | 30471 | 87982 | 86472 | 65818 | 32104 |
| 8.4.9 | Southwestern Appalachians | 61141 | 14531 | 10304 | 8422 | 5821 |
| 8.5.1 | Middle Atlantic Coastal Plain | 114545 | 16124 | 25858 | 17272 | 22159 |
| 8.5.2 | Mississippi Alluvial Plain | 149150 | 337261 | 334998 | 319597 | 370833 |
| 8.5.3 | Southern Coastal Plain | 186085 | 95570 | 86825 | 80677 | 60148 |
| 8.5.4 | Atlantic Coastal Pine Barrens | 20263 | 22794 | 35426 | 36084 | 99628 |
| 9.2.1 | Aspen Parkland/Northern Glaciated Plains | 318674 | 466186 | 519631 | 546675 | 837779 |
| 9.2.2 | Lake Manitoba and Lake Agassiz Plain | 106437 | 403991 | 440897 | 460192 | 452954 |
| 9.2.3 | Western Corn Belt Plains | 218212 | 262681 | 224934 | 223667 | 209025 |
| 9.2.4 | Central Irregular Plains | 134204 | 204341 | 223959 | 238121 | 321836 |
| 9.3.1 | Northwestern Glaciated Plains | 366518 | 251564 | 231664 | 245870 | 563860 |
| 9.3.3 | Northwestern Great Plains | 368298 | 448245 | 460729 | 457994 | 390148 |
| 9.3.4 | Nebraska Sand Hills | 82506 | 46 | 27 | 60 | 4846 |
| 9.4.1 | High Plains | 292621 | 434924 | 488715 | 495241 | 467915 |
| 9.4.2 | Central Great Plains | 272514 | 356382 | 397340 | 404906 | 632890 |
| 9.4.3 | Southwestern Tablelands | 239595 | 364196 | 362126 | 335141 | 293115 |
| 9.4.4 | Flint Hills | 48028 | 113851 | 146532 | 151212 | 154204 |
| 9.4.5 | Cross Timbers | 108973 | 104547 | 117198 | 141406 | 379103 |
| 9.4.6 | Edwards Plateau | 111195 | 113999 | 97552 | 80404 | 27236 |
| 9.4.7 | Texas Blackland Prairies | 65484 | 90892 | 78487 | 87808 | 204468 |
| 9.5.1 | Western Gulf Coastal Plain | 115252 | 270442 | 323841 | 345851 | 502966 |
| 9.6.1 | Southern Texas Plains/Interior Plains and Hills with Xerophytic Shrub and Oak Forest | 192562 | 253019 | 291794 | 296432 | 391367 |
I also specifically summarized changes for boreal ecoregions (4.1, 5.4, 5.1, 3.4, 3.3, 3.2, 3.1, and 6.1) (Table 3):
Table 3. Model-projected changes by boreal ecoregion (sq km):
| NA_L3CODE | NA_L3NAME | curr | rcp45_2050s | rcp45_2080s | rcp85_2050s | rcp85_2080s |
|---|---|---|---|---|---|---|
| 3.1.1 | Interior Forested Lowlands and Uplands | 154744 | 214494 | 244642 | 302972 | 397504 |
| 3.1.2 | Interior Bottomlands | 147095 | 104970 | 89188 | 60760 | 24020 |
| 3.1.3 | Yukon Flats | 43564 | 57030 | 38887 | 47545 | 20218 |
| 3.2.1 | Ogilvie Mountains | 78032 | 84458 | 80561 | 67101 | 40699 |
| 3.3.2 | Hay and Slave River Lowlands | 273770 | 329298 | 260311 | 228498 | 88246 |
| 3.4.3 | Smallwood Uplands | 260456 | 72043 | 45379 | 31847 | 8018 |
| 3.4.4 | Ungava Bay Basin and George Plateau | 124658 | 16561 | 15184 | 14273 | 175 |
| 3.4.5 | Coppermine River and Tazin Lake Uplands | 247484 | 278724 | 261461 | 289089 | 3376 |
| 4.1.2 | Hudson Bay and James Bay Lowlands | 277767 | 56692 | 24743 | 18601 | 4711 |
| 5.1.1 | Athabasca Plain and Churchill River Upland | 261634 | 180539 | 172825 | 169140 | 61254 |
| 5.1.2 | Lake Nipigon and Lac Seul Upland | 217842 | 383191 | 334585 | 292786 | 77691 |
| 5.1.3 | Central Laurentians and Mecatina Plateau | 302052 | 319010 | 262655 | 245088 | 61726 |
| 5.1.4 | Newfoundland Island | 125291 | 159633 | 150097 | 145165 | 141949 |
| 5.1.5 | Hayes River Upland and Big Trout Lake | 264910 | 99563 | 68160 | 60244 | 1195 |
| 5.1.6 | Abitibi Plains and Riviere Rupert Plateau | 287990 | 145527 | 142434 | 111390 | 15384 |
| 5.4.1 | Mid-Boreal Uplands and Peace-Wabaska Lowlands | 384861 | 384235 | 311499 | 240506 | 112622 |
| 5.4.2 | Clear Hills and Western Alberta Upland | 147911 | 76236 | 63250 | 52958 | 8624 |
| 5.4.3 | Mid-Boreal Lowland and Interlake Plain | 137275 | 232935 | 277233 | 324472 | 401337 |
| 6.1.1 | Interior Highlands and Klondike Plateau | 125183 | 86212 | 115739 | 128553 | 19129 |
| 6.1.2 | Alaska Range | 101281 | 86438 | 91774 | 95471 | 35952 |
| 6.1.3 | Copper Plateau | 25317 | 7840 | 1044 | 376 | 21 |
| 6.1.4 | Wrangell and St. Elias Mountains | 58813 | 35893 | 27452 | 23311 | 14394 |
| 6.1.5 | Watson Highlands | 215821 | 109456 | 57769 | 43653 | 6952 |
| 6.1.6 | Yukon-Stikine Highlands/Boreal Mountains and Plateaus | 162769 | 50965 | 43275 | 34939 | 23134 |
This translates into 14% and 42% losses of boreal climate space by 2041-2070 and 2071-2100, respectively, based on RCP 8.5; or 9% and 13% losses based on RCP 4.5
Change projections can be found at http://adaptwest.databasin.org.
References
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